Fail to Star Child in APACHE 9.0 Windows

Question

10-Jun-2020 18:11:00.859 INFO [main] org.apache.catalina.startup.HostConfig.deployDescriptor Deploying deployment descriptor [C:\Tomcat 9.0\conf\Catalina\localhost\balancer.xml] 10-Jun-2020 18:11:00.860 WARNING [main] org.apache.catastrong textlina.startup.HostConfig.deployDescriptor The path attribute with value [/balancer] in deployment descriptor [C:\Tomcat 9.0\conf\Catalina\localhost\balancer.xml] has been ignored 10-Jun-2020 18:11:00.867 WARNING [main] org.apache.catalina.startup.HostConfig.deployDescriptor A docBase [C:\Tomcat 9.0\webapps\balancer] inside the host appBase has been specified, and will be ignored 10-Jun-2020 18:11:00.892 WARNING [main] org.apache.catalina.startup.SetContextPropertiesRule.begin [SetContextPropertiesRule]{Context} Setting property 'debug' to '0' did not find a matching property. 10-Jun-2020 18:11:00.906 SEVERE [main] org.apache.catalina.startup.HostConfig.deployDescriptor Error deploying deployment descriptor [C:\Tomcat 9.0\conf\Catalina\localhost\balancer.xml] java.lang.IllegalStateException: Error starting child at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:720) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:690) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:705) at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:631) at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1830) at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:118) at org.apache.catalina.startup.HostConfig.deployDescriptors(HostConfig.java:526) at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:425) at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1576) at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:309) at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:123) at org.apache.catalina.util.LifecycleBase.setStateInternal(LifecycleBase.java:423) at org.apache.catalina.util.LifecycleBase.setState(LifecycleBase.java:366) at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:936) at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:841) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) at org.apache.catalina.core.StandardService.startInternal(StandardService.java:421) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:930) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) at org.apache.catalina.startup.Catalina.start(Catalina.java:633) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:567) at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:343) at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:474) Caused by: org.apache.catalina.LifecycleException: Failed to start component [org.apache.catalina.webresources.StandardRoot@54e041a4] at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:440) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:198) at org.apache.catalina.core.StandardContext.resourcesStart(StandardContext.java:4792) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:4928) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:717) ... 37 more Caused by: java.lang.IllegalArgumentException: The main resource set specified [C:\Tomcat 9.0\webapps\balancer] is not valid at org.apache.catalina.webresources.StandardRoot.createMainResourceSet(StandardRoot.java:751) at org.apache.catalina.webresources.StandardRoot.startInternal(StandardRoot.java:708) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ... 41 more 10-Jun-2020 18:11:00.916 INFO [main] org.apache.catalina.startup.HostConfig.deployDescriptor Deployment of deployment descriptor [C:\Tomcat 9.0\conf\Catalina\localhost\balancer.xml] has finished in [57] ms